As I have noted many times on this blog, Blashford Lakes would not be anything like as good a site without the invaluable input from our great volunteer team. Our volunteers help out with a range of tasks and do some projects in their entirety.
Over the last week we have had volunteer educators helping with school groups river dipping in the rain, reptile and butterfly surveyors, office administration and our Tuesday and Thursday working parties.
The rarest habitat at Blashford Lakes is the Lichen Heath, perhaps because of its industrial origin it is not actually designated, but it is home to many nationally rare species which form an assemblage which needs looking after.
Lichen Heath close-up
The importance of the area rests on it having very low nutrients, but over time nutrients fall from the sky and collect in the upper layers of the soil as mosses, lichens and small plants die. The obvious conclusion is that it will slowly disappear and turn into nutrient poor acid grassland. So how to keep some areas to true Lichen Heath? The answer is probably to strip off the surface layer and get down to the bare sandy surface and let it colonise once more. This seems very drastic and it feels wrong to be stripping off what is still a diverse sward with lots of interesting species. We started doing this in a small way on Tuesday, doing six small trial plots which we can monitor, if it looks a good technique we can extend it more widely in the years to come.
Lichen heath before surface stripping
Lichen heath after surface stripping
We chose sites where there were small bramble or birch trees that needed removing anyway and piled up the material on the northern side of the scraped area to provide some variation in the surface topography and potentially warm nesting sites for the many species of bees, ants, wasps etc. that call the heath home.
The rain this last week is what allowed us to work on the heath as it meant the lichens absorbed water and so could be walked on gently, in dry conditions they would just crumble to dust under foot, which is why we ask visitors not to walk on it. Even in wet conditions it is intolerant to trampling so we do as little as possible out there. So it was a treat whilst we were there to see some of the special species that grow on the heath including the two rare bird’s-foot trefoils.
Hairy bird’s-foot trefoil
slender bird’s-foot trefoil
On Thursday the volunteers were back on the task of clearing Himalayan balsam and pink purslane from along the Dockens Water. These two invasive alien species can muscle out native species, but can be controlled by pulling them up to prevent seeding. After several years of doing this we have made great progress and balsam is now no more than occasional where once it was the dominant plant. Along the way when doing such tasks we come across other things of interest, one such find was a mating pair of lime hawk-moth.
Lime-hawk moth pair
Some discoveries though are less welcome and one such was an American skunk cabbage plant, the first I have ever heard of along the Dockens Water. This plant has been a big problem in wetland sites across the New Forest and the subject of an eradication program, so finding it here is a worry. I suspect that somewhere up stream someone has it planted around their pond and the seeds are escaping to grow in the wild.
skunk cabbage, a young plant without the huge leaves and yellow flower that attracts water-gardeners.
Our last chance find was made by Geoff, one of our most regular volunteers who photographed this crab spider which had ambushed a bee visiting a daisy flower.
Crab spider with bumble-bee prey on ox-eye daisy.
I will endeavour to do a wildlife update for the week later, I know we have received a number of fabulous photographs from visitors.